INDIANAPOLIS — Heavy smoke from the Canadian wildfires is permeating the atmosphere in Indiana, and that will continue through Wednesday. Local officials issued a Knozone Action Day for the city of Indianapolis.
It's a situation we've seen before.
Last April, an accumulation of hazardous chemicals and fine toxic particles swirling in the air prompted an extension to Air Quality Days in Randolph and Wayne Counties following a massive recycling plant fire in Richmond, while officials in Indianapolis were also motivated to issue a Knozone Action Day due to air pollution that same day.
Some months later, we're seeing a similar situation play out.
The Indiana Department of Environmental Management issued an Air Quality Day, while the Office of Sustainability issued a Knozone Action Day as fine particular matter puts large swaths of the Midwest in a chokehold.
Back in April when the dual air quality alerts were issued, environmental officials told 13News that while the declarations - the Air Quality Days and Knozone Action Day - could be issued at the same time, or even on the same day, they could sometimes be made for different reasons.
Knozone Action Day can be issued due to ground level ozone pollution concerns or fine particulate matter pollution, whereas the Air Quality Days issued by the Indiana Department of Environmental Management are made when officials forecast elevated levels of fine particles, specifically PM2.5, are in the air.
Meanwhile the Knozone Action Days, issued for central Indiana by the Office of Sustainability, are sometimes issued due to unhealthy ground level pollution throughout the area or when there's an excess of fine particulate matter.
As Indianapolis continues to experience some of the worst air pollution in the world, the Knozone Action Day and Air Quality Days most recently issued do stem from an abundance of fine particulate matter circulating in the air from Canadian wildfires.
"Knozone Action Days can be triggered by elevated levels of either - or in some cases both ozone or fine particulate matter - PM2.5," said Lindsay Trameri, who is a Community Engagement Manager for The Office of Sustainability, a division of the Department of Public Works, back in April.
Here's a further breakdown of the difference in pollution.
Particulate matter vs. ground level ozone
Ground level ozone, also called tropospheric ozone, is not emitted directly into the air and does not have a direct emissions source.
Rather, it is created through chemical reactions that happen when oxides of nitrogen and volatile organic compounds interact with sunlight.
Pollutants that are put off by cars, power plants, industrial boilers, refineries, chemical plants, and other sources chemically react to the presence of sunlight to create this tropospheric ozone that's not only dangerous for human health, but also a major contributor to climate change.
Even relatively low levels of ground ozone can cause health effects, according to the U.S. Environmental Protection Agency, who said children are at greatest risk from "exposure to ozone because their lungs are still developing" and they are "more likely to be active outdoors" when ozone levels are high.
Depending on the level of exposure, ground ozone can cause coughing and sore or scratchy throat. Exposure can make it more difficult to breathe deeply and vigorously, and can make breathing painful. Officials think that's what's happening now in Indianapolis.
"Ground-level ozone is the primary contributor to smog in urban areas. Smog is formed when harmful emissions from sources like cars and lawnmowers react with heat and sunlight," the Office of Sustainability said in a statement.
Fine particulate matter, however, is another type of air pollution that can have major adverse affects on human health. Unlike ground ozone, it's considered to be a direct source of pollution, being sourced from soot from fires, dust, factory debris, or fossil fuel emissions, which are all examples of particulate matter.
In the Richmond case, the fire burning at the recycling plant would be a direct source for the distribution of this toxic, fine particulate matter into the air.
Fine particulate matter are often referenced by their size, so you could have PM2.5 or PM10 particulate matter, which indicate for how large the tiny droplets or particles actually are.
PM2.5 is of special concern to public health officials, because their small size allow them to deposit into the deepest parts of a human lung and into our bloodstream. Larger PM10 particles can also still settle into our lungs and bodies, but because PM10 can also include PM2.5, that particulate size is referenced more often.
Exposure to PM2.5 particles is something the World Health Organization has named as a major contributor to declines in human health. Exposure to PM2.5 has been linked to premature death in people with heart or lung disease, nonfatal heart attacks, and irregular heartbeats. One study from Harvard found more exposure to PM2.5 is linked to higher rates of death from Covid-19.
To protect residents and local air quality, the Office of Sustainability said they issue Knozone Action Days whenever ozone or fine particulate matter levels rise above a certain threshold.
Indianapolis residents are already dealing with the impact of polluted air from both ground ozone and PM2.5. The Office of Sustainability estimated 10.9% of city residents live with asthma, while 8.6% of Indianapolis residents live with COPD. Both those figures are higher than the national average, according to the department.
Scientists affiliated with the Office of Sustainability said they would also continue to monitor the levels of PM2.5 caused by wildfire smoke out west over the coming days and weeks.
Residents are encouraged to reduce their contribution to fine particulate matter pollution through:
- Never burn trash, furniture, leaves, or grass clippings. Burning these items is always illegal in Marion County and punishable by fines up to $2,500. If you encounter illegal open burning, utilize the RequestIndy mobile app or website or call the Mayor's Action Center at 317-327-4622. If it's an emergency, call 911.
- Avoid campfires, bonfires, and barbecues until the air quality returns to healthy levels. The rules and regulations for open burning are available on the Department of Business and Neighborhood Services' website: indy.gov/BNS
Residents are encouraged to reduce their contribution to ground-level ozone through:
- Avoid vehicle idling, including when in drive-thru lanes or picking up carry-out
- Use active forms of transportation like walking or biking
- Utilize public transportation or carpool with services such as IndyGo or Commuter Connect
- Wait to refuel and mow until after 7 p.m.
- Combine errands to reduce number of trips
- Conserve energy by turning off lights or setting the air conditioner to 75 degrees or above
- Delay use of garden, household, and workshop chemicals until air has returned to healthy levels
- Never burn trash. Burning trash is illegal in Marion County, and the rules and regulations for open burning are available on the Department of Business and Neighborhood Services' website: indy.gov/BNS
This will be the first Knozone Action Day for 2023, and comes just weeks after Indianapolis was named one of the worst polluted major cities in the United States in a global report.
Data collected from more than 30,000 air quality monitoring stations across 7,323 locations in 131 countries, territories, and regions was analyzed by IQAir’s air quality scientists for the study.
In the U.S., IQAir claims the most polluted major cities were Columbus, Ohio, followed by Atlanta, Chicago, Indianapolis and Dallas. Detroit also suffered from high levels of air pollution.
Air quality in Columbus hit 13.1 micrograms of PM 2.5 particles per cubic meter in 2022 according to the study, making it the most polluted major city in the U.S.
WHO first published air quality guidance in 2005, and made the benchmark for acceptable levels of air pollution less than 10 micrograms of PM2.5 per cubic meter. They changed those guidelines to below 5 micrograms per cubic meter in 2005.
Indianapolis had an average PM2.5 concentration of 11.3 in 2022, according to the report.